Every line of text is drawn within a bounding box determined by
the Doc.Rect
property. The justification property can be used to space out words
so that they fit the bounding box exactly.

Typically, you will only need to use values of zero - no
justification - and one - full justification. However, intermediate
values can be used to partially justify text.

As each line is drawn, the difference between the width of the
line and the width of the bounding box is evaluated to determine
the amount of free width. This free width is divided by the number
of space characters in the line and then multiplied by the
justification factor to produce an inter-word spacing for the line.
Lines at the end of paragraphs are not justified.